77. Validate Configuration Register Layout

#include <stdio.h>
#include <stdint.h>

typedef struct {
    unsigned short reg;
} ConfigRegister;

int validate_config(ConfigRegister *cfg) {
    // Write logic using pointer access
    uint8_t bit0 = cfg->reg & 1;
    uint8_t bit23 = (cfg->reg >> 1) & 3;
    uint16_t bits = (cfg->reg >> 4) & 0xFF;
    if (bit0 == 1 && bit23 != 3 && bits == 0) {
        return 1;
    }
    else {
        return 0;
    }
}

int main() {
    ConfigRegister cfg;
    scanf("%hx", &cfg.reg);

    int result = validate_config(&cfg);
    printf("%d", result);

    return 0;
}